RNAProtein160-page7 - on the DNA. Elongation RNA polymerase...

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Gene Expression – DNA to Protein - 7 How it works: Details of Transcription and Translation RNA synthesis, or transcription, uses DNA as a template, and occurs in the nucleus. There are three stages in transcription: Initiation, Elongation and Termination. Recall that all RNA is synthesized by transcription, although we focus on the synthesis of mRNA in our discussions. Initiation The region of DNA that codes for the specific gene to be transcribed starts to unwind using the enzyme, RNA polymerase, to initiate the process. Transcription is started at a region of the DNA molecule called the promoter, a specific DNA base sequence at the 3' of each gene. A promoter determines the template strand of the DNA and where transcription will start. Special proteins, called transcription factors, help RNA polymerase find the promoter regions
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Unformatted text preview: on the DNA. Elongation RNA polymerase will move in the 3' to 5' direction along the DNA template during what is now called the elongation process of transcription. Like DNA, RNA is synthesized in the 5' to 3' direction from the 3' to 5' DNA template. Only one strand of the DNA molecule, the template strand, is transcribed. The complement strand, which is not transcribed, is called the non-template strand (or sometimes the complementary strand or non-coding strand). RNA Nucleotides are added to the chain according to the complementary base pairing; that is: RNA A - DNA T RNA U - DNA A RNA C - DNA G RNA G - DNA C The DNA molecule will start rewinding after about 10 RNA nucleotides have been joined to the mRNA chain....
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